1. Field of the Disclosure
The present disclosure relates to a sprinkler including both pressure regulation and flow throttling provided in the nozzle assembly.
2. Related Art
Several major irrigation equipment manufacturers manufacture sprinklers which have pressure regulators incorporated into the sprinkler riser to which a nozzle assembly is attached. See, for example, U.S. Pat. No. 5,779,148. The pressure regulator may provide a relatively constant pressure to the attached nozzle assembly over a relatively wide range of flow rates and upstream nozzle assembly pressures for ¼, ½ or full circle nozzles.
Pressure compensating insertable elastomeric washers are manufactured to provide some pressure compensation with a different color code designating different nozzle flow rates. These washers, however, have limited flow and pressure ranges as provided by the deflection of an elastomeric disc with a sharp edge hole in the center which when the upstream pressure is high bend the elastomeric flow limiting disc with sharp edge hole and reduce the diameter of the upstream sharp edge. These pressure compensating washers may be incorporated into the nozzle assemblies or filter assemblies of existing sprinklers. As many as 12 or more may be necessary depending on the manufacturer to cover a range of flows for ¼, ½ and full circle sprinklers.
Co-pending U.S. patent application Ser. No. 12/348,864 filed Jan. 5, 2009 entitled ARC AND RANGE OF COVERAGE ADJUSTABLE STREAM ROTOR SPRINKLER and Ser. No. 11/438,796 entitled PRESSURE REGULATING NOZZLE ASSEMBLY filed May 22, 2006 discuss additional background information and are hereby incorporated by reference herein in their entirety.